From: Heiko Carstens <hca@xxxxxxxxxxxxx>
[ Upstream commit 81e8479649853ffafc714aca4a9c0262efd3160a ]
Commit bb1520d581a3 ("s390/mm: start kernel with DAT enabled") did not
implement direct map accounting in the early page table setup code. In
result the reported values are bogus now:
$cat /proc/meminfo
...
DirectMap4k: 5120 kB
DirectMap1M: 18446744073709546496 kB
DirectMap2G: 0 kB
Fix this by adding the missing accounting. The result looks sane again:
$cat /proc/meminfo
...
DirectMap4k: 6156 kB
DirectMap1M: 2091008 kB
DirectMap2G: 6291456 kB
Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled")
Reviewed-by: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/s390/boot/vmem.c | 19 ++++++++++++++++---
arch/s390/include/asm/pgtable.h | 2 +-
arch/s390/mm/pageattr.c | 2 +-
3 files changed, 18 insertions(+), 5 deletions(-)
--- a/arch/s390/boot/vmem.c
+++ b/arch/s390/boot/vmem.c
@@ -10,6 +10,10 @@
#include "decompressor.h"
#include "boot.h"
+#ifdef CONFIG_PROC_FS
+atomic_long_t __bootdata_preserved(direct_pages_count[PG_DIRECT_MAP_MAX]);
+#endif
+
#define init_mm (*(struct mm_struct *)vmlinux.init_mm_off)
#define swapper_pg_dir vmlinux.swapper_pg_dir_off
#define invalid_pg_dir vmlinux.invalid_pg_dir_off
@@ -126,7 +130,7 @@ static bool can_large_pmd(pmd_t *pm_dir,
static void pgtable_pte_populate(pmd_t *pmd, unsigned long addr, unsigned long end,
enum populate_mode mode)
{
- unsigned long next;
+ unsigned long pages = 0;
pte_t *pte, entry;
pte = pte_offset_kernel(pmd, addr);
@@ -135,14 +139,17 @@ static void pgtable_pte_populate(pmd_t *
entry = __pte(_pa(addr, mode));
entry = set_pte_bit(entry, PAGE_KERNEL_EXEC);
set_pte(pte, entry);
+ pages++;
}
}
+ if (mode == POPULATE_DIRECT)
+ update_page_count(PG_DIRECT_MAP_4K, pages);
}
static void pgtable_pmd_populate(pud_t *pud, unsigned long addr, unsigned long end,
enum populate_mode mode)
{
- unsigned long next;
+ unsigned long next, pages = 0;
pmd_t *pmd, entry;
pte_t *pte;
@@ -154,6 +161,7 @@ static void pgtable_pmd_populate(pud_t *
entry = __pmd(_pa(addr, mode));
entry = set_pmd_bit(entry, SEGMENT_KERNEL_EXEC);
set_pmd(pmd, entry);
+ pages++;
continue;
}
pte = boot_pte_alloc();
@@ -163,12 +171,14 @@ static void pgtable_pmd_populate(pud_t *
}
pgtable_pte_populate(pmd, addr, next, mode);
}
+ if (mode == POPULATE_DIRECT)
+ update_page_count(PG_DIRECT_MAP_1M, pages);
}
static void pgtable_pud_populate(p4d_t *p4d, unsigned long addr, unsigned long end,
enum populate_mode mode)
{
- unsigned long next;
+ unsigned long next, pages = 0;
pud_t *pud, entry;
pmd_t *pmd;
@@ -180,6 +190,7 @@ static void pgtable_pud_populate(p4d_t *
entry = __pud(_pa(addr, mode));
entry = set_pud_bit(entry, REGION3_KERNEL_EXEC);
set_pud(pud, entry);
+ pages++;
continue;
}
pmd = boot_crst_alloc(_SEGMENT_ENTRY_EMPTY);
@@ -189,6 +200,8 @@ static void pgtable_pud_populate(p4d_t *
}
pgtable_pmd_populate(pud, addr, next, mode);
}
+ if (mode == POPULATE_DIRECT)
+ update_page_count(PG_DIRECT_MAP_2G, pages);
}
static void pgtable_p4d_populate(pgd_t *pgd, unsigned long addr, unsigned long end,
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -34,7 +34,7 @@ enum {
PG_DIRECT_MAP_MAX
};
-extern atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX];
+extern atomic_long_t __bootdata_preserved(direct_pages_count[PG_DIRECT_MAP_MAX]);
static inline void update_page_count(int level, long count)
{
--- a/arch/s390/mm/pageattr.c
+++ b/arch/s390/mm/pageattr.c
@@ -41,7 +41,7 @@ void __storage_key_init_range(unsigned l
}
#ifdef CONFIG_PROC_FS
-atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX];
+atomic_long_t __bootdata_preserved(direct_pages_count[PG_DIRECT_MAP_MAX]);
void arch_report_meminfo(struct seq_file *m)
{
